Former editor of the Communist party Daily Worker newspaper and later defector Louis Budenz describes Eisler as one who "ordered party leaders about with a sharpness and even brutality of manner that suited well the Gauleiter of a ruthless dictatorship. Budenz quotes Eisler outlining Soviet Far Eastern policy at a CPUSA Politburo meeting saying in 1936, "This USA-USSR collaboration, we understand, comrades, would eventually make the Pacific a Soviet lake. That would give the Soviet fatherland the power to defend itself against American imperialism, after having won the original aid of the United States against Japanese imperialism."
Shortly thereafter Eisler traveled to the Spanish Civil War zone. Eisler reentered the United States illegally in 1941.

In the November 1942 issue of The Communist Eisler wrote an article demanding all-out American action for the Second Front and belaboring Americans for permitting "prejudice" to blind them to the virtues of Soviet Russia.

Although accused of espionage after World War II, he was never charged with violating U.S. laws apart from misrepresenting his Communist Party affiliation on his emigration application. Newsweek (February 23, 1948) described him as the "Number One Red Agent" in the U.S.

In a dramatic escape in 1950, Eisler secretly boarded a Polish freighter bound for London and was discovered by the crew after the ship was at sea. Once in England, authorities allowed him to leave for the German Democratic Republic, where Eisler became chief of East German radio and a leading propaganda voice for the Communist government.

After his death, several schools and streets in the GDR were named in his honor.

References

Investigation of Un-American Propaganda Activities in the United States, hearings of 6 February 1947, U.S. Congress, House of Representatives, Committee on Un-American Activities, 80th Cong., 1st sess., 14–19.